The known forces of nature can be dividedinto four classes, viz., gravity,electromagnetism, weak nuclear force andstrong nuclear force. With reference to them,which one of the following statements is notcorrect?

• A. Gravity is the strongest of the four
• B. Electromagnetism acts only on particles withnan eclectic charge
• C. Weak nuclear force causes radioactivity
• D. Strong nuclear force holds protons andnneutrons inside the nucleus of an atom